Here's the scenario:
I have a main server and a backup server park. Due to the setup, there are port forwards active on my router to one specific ip address. Of course, I could make reservations for the backup server park too, but that would mean that I would duplicate all the servers for RDP and other services to match the new ip too.
Given that they are to substitute the other in case one goes down for maintenance, I was wondering if the following scenario is possible, and what the drawbacks are:
Have both servers listed on the DHCP server to get the same MAC Address and a second ip address.
If the first server gets an ip from the DHCP server, it uses the main address from the reservations. If the second server then comes online, it tries to claim the first main address from the DHCP, but fails, then automatically gets the second IP address.
Obviously, if the first server goes offline, the second will not automatically get the other IP Address. I'm aware of that, but that's not really the issue.
Basically in case the main server goes offline, I want to log into the second server, refresh its IP and everything works again. The easiest method is simply restarting the router which causes a network wide restart of all network interfaces giving all a new ip address.
The DHCP server is on a domain controller that runs windows server 2016, though the backup one has 2008 R2, but I'm pretty sure DHCP hasn't changed.
If I were able to do portforwarding based on hostname, the problem would've been solved already, but I can't.
So, is the above possible, and if so, are there any drawbacks or things I have to keep in mind? Any advice why this is a terrible idea, feel free to place them in the comments. :)